To not hijack this thread but a colleague of mine that provides ammunition suggests the Federal 210M primer. Why, I have no idea as he was hoping not to present me proprietary information. I will use the Lee Hand Priming Device Once i get all over to utilizing the Feds. https://215-federal-primers-for-s01345.aboutyoublog.com/34383275/the-5-second-trick-for-federal-large-rifle-benchrest-primers